Ngauruhoe

Ngauruhoe is the largest, youngest and most active cone of the much larger Tongariro Volcano complex. It lies within Tongariro National Park between Tongariro to the north and Ruapehu to the south. At 2291m high it is the highest point of the Tongariro complex.

Like Taranaki and Ruapehu, Ngauruhoe is a stratovolcano (or composite cone volcano) made of alternating layers of ash, scoria and andesite lava flows. The sides of the cone are steep, loose scree slopes covered in material from recent eruptions. Fumaroles exist in the inner crater and on the rim of the eastern and northern outer crater. Steam is seldom visible above the crater rim.

The cone started to build up at least 2500 years ago, although recent research suggests it may be up to 7000 years old.

Māori oral history records many eruptions prior to European colonisation, and there have been more than 60 eruptions since written records began in 1839. Most have been ash eruptions but a few have included lava flows.

Typically Ngauruhoe has erupted at least every 9 years but there has been no eruption since 1975, and the last lava flow from Ngauruhoe was in 1954. In 1973 red hot blocks of lava were ejected and during 1974 and 1975 ash eruptions continued with lava blocks thrown as far as 3km away.

Ngauruhoe was also used as Mt Doom by Peter Jackson in his Lord of the Rings Trilogy.